In a medium bowl, whisk together the oil, apple cider vinegar, orange juice, shallots, honey, mustard, cayenne pepper, poppy seeds and salt. Cover and refrigerate for one hour.
Toss alfalfa sprouts and orange zest with 6 tablespoons vinaigrette; set aside.
In a large bowl, toss together the mixed greens, strawberries, blueberries and sunflower seeds. Pour remaining vinaigrette over salad and toss.
Divide greens and strawberries among 8 plates and place a mound of dressed sprouts on the side.